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Comment: Re: Fusion Confusion (Score 5, Interesting) 287

by gewalker (#47708351) Attached to: If Fusion Is the Answer, We Need To Do It Quickly

Well, since the whole purpose of fusion reactors is to make commercially useful power, it is pretty clear that we do not have a working fusion reactor by any reasonable definition.

Despite having spent billions (22 Billion USD on hot fusion research by US alone) on the problem so far, with billions yet to come, we do not have working fusion reactors. Even ITER will just be a prototype with no power generation at all. Cost to develop commercially, unknown but bound to be a lot of money.

The US alone has also spent around 15 Billion developing Fast Breeder reactors, and has little to show for it. Other countries have similar experience.

Estimated cost to develop commercial LFTR reactors seems to be in the range 3 - 20 Billion USD. A commercial LFTR prototype seems to be likely 1 billion USD by most observers.

And you still have to build the reactors -- that won't be cheap either. Every known possible solution to replacing our energy infrastructure has a large economic cost, and significant to large environmental cost as well. Kind of the way large-scale engineering works.

Yet the cost of doing nothing will be larger yet, at least eventually. Peak fossil fuel is coming sooner or later, even if you master shale and methane hydrates with high recovery rates and limited environmental impact. There are a lot of third-world people in this world that would gladly join the first-world lifestyle which puts a severe constraint on expanding fossil fuels usage to match the growth in demand.

Personally, the combination of LFTR and renewable sources seems most likely to me to be commercially successful by 2050. Why, because the needed development seem to be within or nearly withing the capabilities of current engineering in both cases. Engineers are very happy to deliver good enough when the perfect seems unattainable.

Comment: Re:KSP (Score 2) 201

by gewalker (#47580947) Attached to: NASA Tests Microwave Space Drive

No, the question is how fast can it accelerate the average potato. NASA reported 30-50 mN of thrust., call it 40. The average potato is about 375 grams, call is 400 even so math is real east. F=m*a or a = F / M or 1e-7 m/sec^2. So, accelerate for 1 year and you reach the break-neck speed of 31.5 meters per second or 70.5 mph

It is going to take a long time to get that potato to Alpha Centauri. Especially considering that you have to also accelerate the mass of the Q-drive unit itself and the energy source to supply the Q-drive.

Now if the effect is real and the efficiency and can be improved you still have something potentially useful in-deed for satellites. You could even maneuver asteroids if you had lots of patience.

Comment: Re:Time to start building more nuke plants as long (Score 3, Insightful) 288

by gewalker (#47539527) Attached to: Greenpeace: Amazon Fire Burns More Coal and Gas Than It Should

TMI safety both failed and succeeded depending upon how you look at things.

It failed to prevent a partial meltdown of the reactor core.

It failed to prevent a significant release of radiation to the general environment as 15 curies (560 GBq) of iodine-131 (the most concering portion due to biological uptake to the thyroid)

It succeeded in terms of avoiding the wide-scale problems of Fukushima or Chernobyl

It failed in terms of public opinion of nuclear power being a reasonably source of energy production. Nuclear plant construction in US was virtually shut down after this, no new licenses till 2012.


Comment: Re:... and that's not much. (Score 1) 190

Cs-237 is pretty hot, half life of about 30 yrs. How about

Pu-239 .435 kg
U-235 12500 kg
U-238 80,400 kg.

I am sure these sound scary to most people, though Cs-237 is presumably a significant component of the nuclear release in question.

Of course they sound much worse because you can make nukes out of these and that increases the radiation release rate by many orders of magnitude and that mushroom cloud, etc.

To Americans it's Cesium not Caesium, then again most American don't really know what that it is. And most don't understand radiation either.

Comment: Re:I also measure distance (Score 2) 190

Conveniently, there is an even better comparison. You have to disperse all of the radioactive soil into the air to make a similar comparison. We don't actually pump soil into the air though. We do however burn coal.

Webpage According to the National Council on Radiation Protection and Measurements (NCRP), the average radioactivity per short ton of coal is 17,100 millicuries/4,000,000 tons, or 0.00427 millicuries/ton. This figure can be used to calculate the average expected radioactivity release from coal combustion.

Converting this to metric equates to about 0.174 MBq/ton (metric ton).

WebpageLargest coal plant in America burns 11 millions tons of coal per year.

Now 11,000,000 tons * 0.174 MBq / ton is 1.914e6 MBq -- a bit less than the twice the totally scary 1 trillion Bq

The average coal plant burns coal with around 0.5 trillion Bq / year

Now, not all of the radiation get released into the atmosphere, a lot of it ends up in the ash. But the ash is stored in ponds and left in piles on the ground, so its not a terrible improvement in terms of safe radioactive containment.

Comment: Re:Good (Score 1) 342

I would settle for nice modular neighborhood-scale TFTR reactors for now. I don't expect to see Mr. Fusion in the years I have left. I don't expect Congress to contribute to either of these either. I might wish they get rid of some unneeded regulations, but I have little hope of this happening either.

Comment: Saying something good about ComCast hurts my brain (Score 4, Insightful) 146

by gewalker (#47524437) Attached to: Comcast Carrying 1Tbit/s of IPv6 Internet Traffic

In actual fact, the ComCast internet service is not too bad. It is just their customer support, pricing, monopoly status and general arrogance that make them among the most hated company in existence.

The other interesting thing in the article was Google showing their IPv6 traffic was now around 4% up looked the perhaps the upward bend at the beginning of an s-Curve.

Comment: Re:headed in the wrong direction (Score 1) 230

by gewalker (#47491897) Attached to: EPA Mulling Relaxed Radiation Protections For Nuclear Power

According to scientist, the common view is that the linear no-threshold model is actually the flawed viewpoint. See this article for a pro-radiation view that is not commonly reported. Although most people will scoff, there is actual evidence that a little ionizing radiation is good for you.

Yes, I would participate in the study that installs a radioactive source in your house (at reasonably low levels) because I believe the data that I have been able to find in the past.

White dwarf seeks red giant for binary relationship.